Free Class C Subnetting Tutorial, IP Address Subnetting, How to subnet Class C network

This lesson is only a part of a series of IPv4 subnetting lessons. All the basic concepts about subnetting are explained in Class C Subnetting Tutorial - Part 1 lesson. You must visit Class C Subnetting Tutorial - Part 1 lesson to understand the basic concepts of subnetting. Please visit below links in order to learn IPv4 subnetting completely.

• Class C Subnetting Tutorial - Part 1
• Class C Subnetting Tutorial - Part 2
• Class B Subnetting Tutorial - Part 1
• Class B Subnetting Tutorial - Part 2
• Class A Subnetting Tutorial - Part 1
• Class A Subnetting Tutorial - Part 2
• Variable Length Subnet Masking (VLSM)
• Supernetting

Class C 4-bit subnetting

If we include four bits from the host part to the network part in the last octet, the default subnet mask of Class C network is changed to The four bits added to the network part from the host part, in the last octet, can have sixteen possible values. Those sixteen possible values are 0000, 0001, 0010, 0011, 0100, 0101, 0110, 0111, 1000, 1001, 1010, 1011, 1100, 1101, 1110 and 1111.

That means, we get sixteen subnets if we do a 4-bit subnetting for a Class C network.

Please refer below image.


SN No Description Binaries Decimal
1 Network Address 11000000.10101000.00001010.00000000
First IPv4 address 11000000.10101000.00001010.00000001
Last IPv4 address 11000000.10101000.00001010.00001110
Broadcast Address 11000000.10101000.00001010.00001111
2 Network Address 11000000.10101000.00001010.00010000
First IPv4 address 11000000.10101000.00001010.00010001
Last IPv4 address 11000000.10101000.00001010.00011110
Broadcast Address 11000000.10101000.00001010.00011111
3 Network Address 11000000.10101000.00001010.00100000
First IPv4 address 11000000.10101000.00001010.00100001
Last IPv4 address 11000000.10101000.00001010.00101110
Broadcast Address 11000000.10101000.00001010.00101111
4 Network Address 11000000.10101000.00001010.00110000
First IPv4 address 11000000.10101000.00001010.00110001
Last IPv4 address 11000000.10101000.00001010.00111110
Broadcast Address 11000000.10101000.00001010.00111111
5 Network Address 11000000.10101000.00001010.01000000
First IPv4 address 11000000.10101000.00001010.01000001
Last IPv4 address 11000000.10101000.00001010.01001110
Broadcast Address 11000000.10101000.00001010.01001111
6 Network Address 11000000.10101000.00001010.01010000
First IPv4 address 11000000.10101000.00001010.01010001
Last IPv4 address 11000000.10101000.00001010.01011110
Broadcast Address 11000000.10101000.00001010.01011111
7 Network Address 11000000.10101000.00001010.01100000
First IPv4 address 11000000.10101000.00001010.01100001
Last IPv4 address 11000000.10101000.00001010.01101110
Broadcast Address 11000000.10101000.00001010.01101111
8 Network Address 11000000.10101000.00001010.01110000
First IPv4 address 11000000.10101000.00001010.01110001
Last IPv4 address 11000000.10101000.00001010.01111110
Broadcast Address 11000000.10101000.00001010.01111111
9 Network Address 11000000.10101000.00001010.10000000
First IPv4 address 11000000.10101000.00001010.10000001
Last IPv4 address 11000000.10101000.00001010.10001110
Broadcast Address 11000000.10101000.00001010.10001111
10 Network Address 11000000.10101000.00001010.10010000
First IPv4 address 11000000.10101000.00001010.10010001
Last IPv4 address 11000000.10101000.00001010.10011110
Broadcast Address 11000000.10101000.00001010.10011111
11 Network Address 11000000.10101000.00001010.10100000
First IPv4 address 11000000.10101000.00001010.10100001
Last IPv4 address 11000000.10101000.00001010.10101110
Broadcast Address 11000000.10101000.00001010.10101111
12 Network Address 11000000.10101000.00001010.10110000
First IPv4 address 11000000.10101000.00001010.10110001
Last IPv4 address 11000000.10101000.00001010.10111110
Broadcast Address 11000000.10101000.00001010.10111111
13 Network Address 11000000.10101000.00001010.11000000
First IPv4 address 11000000.10101000.00001010.11000001
Last IPv4 address 11000000.10101000.00001010.11001110
Broadcast Address 11000000.10101000.00001010.11001111
14 Network Address 11000000.10101000.00001010.11010000
First IPv4 address 11000000.10101000.00001010.11010001
Last IPv4 address 11000000.10101000.00001010.11011110
Broadcast Address 11000000.10101000.00001010.11011111
15 Network Address 11000000.10101000.00001010.11100000
First IPv4 address 11000000.10101000.00001010.11100001
Last IPv4 address 11000000.10101000.00001010.11101110
Broadcast Address 11000000.10101000.00001010.11101111
16 Network Address 11000000.10101000.00001010.11110000
First IPv4 address 11000000.10101000.00001010.11110001
Last IPv4 address 11000000.10101000.00001010.11111110
Broadcast Address 11000000.10101000.00001010.11111111


The network is divided into sixteen subnets, each subnet has 16 total IPv4 addresses and 14 usable IPv4 addresses. Two IPv4 addresses are used in each subnet to represent the network address and the directed broadcast address.

Class C Subnetting can be summerized as below.

Subnet Bits Subnet Mask CIDR Total Subnets Usable IPs/Subnet
0 /24 1 254
1 /25 2 126
2 /26 4 62
3 /27 8 30
4 /28 16 14
5 /29 32 6
6 /30 64 2


In this Class C Subnetting Tutorial - Part 2 lesson, you have learned how to perform a Class C 4-bit subnetting. If you practice previous lesson examples and the above example in this lesson, you can clearly understand how to subnet a Class C network. Try to practice and find yourself the network address, usable IPv4 address range and the directed broadcast address of remaining 5-bit and 6-bit Class C subnets.

Click the following link to visit previous lesson to learn Class C 1-bit, 2-bit and 3-bit subnetting. To view and learn Class B Subnetting Tutorial - Part 1, Click "Next".

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Class C Subnetting Tutorial - Part 1
Class B Subnetting Tutorial - Part 1
Class B Subnetting Tutorial - Part 2
Class A Subnetting Tutorial - Part 1
Class A Subnetting Tutorial - Part 2
Variable Length Subnet Masking (VLSM)
How to find out the Network Address and Broadcast Address of a subnetted IPv4 address